1. Field of the Invention
This invention relates to a bus simulation apparatus and a bus simulation program for simulating a bus connecting a microprocessor, a peripheral device and the like.
2. Description of the Related Art
For instance, Japanese Laid-open Publication No. 07-121405 discloses the related art wherein a target machine actually operating software is simulated by a multipurpose calculator different from the machine for testing or debugging of the software.
The MPU simulator described in this gazette is for simulating a microprocessor, while an I/O model is for simulating the input and output device. An I/O monitor is for simulating a group of signals for connecting the microprocessor and the input/output device.
These MPU simulator, I/O model and I/O monitor work by means of a separate calculator or a separate process. Therefore, in order to simulate the transmission and receipt of signals between the microprocessor and the input/output device, the inter-calculator communication or the inter-process communication must be performed between the MPU simulator, the I/O model and the I/O monitor. As the inter-calculator communication or the inter-process communication, the socket communication is used, for example.
However, where a procedure for the socket communication or the like is implemented into the MPU simulator, the I/O model and the I/O monitor respectively, the implementation should depend on the connection between the microprocessor and the input/output device. This adversely affects on the preparing performance of the MPU simulator, and etc. In addition, even if the MPU simulator, the I/O model and the I/O monitor is made to work by a separate calculator or a separate process, when any change is made on the design of the connecting relation, it becomes hard to cope with such change by reusing the MPU simulator, the I/O model and the I/O monitor. Likewise, it is hard to port the MPU simulator, the I/O model and the I/O monitor to a system based on the other design. As a matter of course, the more the number of MPU simulators increases, the greater these difficulties become remarkably.
In the socket communication, it occurs that the relation between a server and a client is formed between the communication objects. Where the relations between the server and the client are complicated among the MPU simulator, the I/O model and the I/O monitor, the processing like the debugging is easy to be under the influence of the starting order, and it contributes to the loss of stability of the working performance.